drm/msm: Add kernel side submit profiling and tracing

Record the GPU always on timer value at the start and end of a
submission on the ringbuffer. Since the timer runs at a constant
19.2 Mhz this is a handy way of tracking how long each
submission takes.

The timer values are recorded in the memptrs. Each ringbuffer is
given a circular list of 128 entries to store the event ticks;
this should be enough to avoid running out of room even when the
ring is completely full of submissions.

Add trace events for the user to track when submissions are
queued, submitted to the ringbuffer and retired. The submitted
trace point shows the GPU ticks and the current kernel time at
submit time (as read by the CPU) and the retired trace event shows
the GPU ticks at submission start/end as read by the GPU. Taken
together these two events can provide a pretty close match between
the current GPU time and the kernel time which is handy for tracing
tools that try to match up the various kernel events with one
another.

Change-Id: Ic0dedbadbcf89f032890820785b9fb49a6362b01
Signed-off-by: Jordan Crouse <jcrouse@codeaurora.org>

0 files changed, 0 insertions, 0 deletions